| 392 / | HD | ELECTRIC RESISTANCE HEATING DEVICES |
| * | DD | HEATING DEVICES (CLASS 219 SUBCLASS 200) {11} |
| 311 | DF | .~ Fluid-in-circuit type heater {6} |
| 324 | DF | .~.~ Steam or vapor generator {2} |
| 333 | DF | .~.~.~ Manually filled tank or container {3} |
| 336 | DF | .~.~.~.~ Separate electrode compartment {1} |
| 337 | ![]() | .~.~.~.~.~ Electrode compartment removable from tank |